At the very beginning of April, this does not look like "the cruelest of months" unless the exceptional fine weather is pushing the season and the days of spring will soon loose the flowers of the celandine, trout lilies, spring beauties, Dutchman breeches, trilliums, Virginia bluebells and primroses, all of which are already out, and only dandelions will remain. On the edge of the farm field a black cherry is in full bloom and the oaks are on the point of releasing their flowers from the swollen buds. I have the impression that this winter's heavy snows (55" in toto), hit by the sun kept the soil from freezing very deep so that the warmer temperatures of the last two weeks were enough to awaken the roots of everything. On the 18th of March I sowed a mixture of lettuces, mesclun and Asian peas (for their young shoots) and the plot has a wash of green and soon will allow me to put John Evelyn's advice to the test (see my blog on his "salad bowl"). 3/22/13: last week was cool, wet with night frost, now, the 2nd day of spring, there was light snow overnight and a high in the mid 30s. The veg. beds were rototilled on the 10th, but have been too wet to rake out: nothing sowed yet other than the salads.
Birdwise the first three months of 2010 were sort of tame and they were not improved by the reading of The Wisdom of Birds. An Illustrated History of Ornithology, by Tim Birkhead, a Professor at the University of Sheffield, England, which had been praised by the book review editor of Birding. I found in it a great deal of interest. Having proposed to German colleagues that the 17th century Englishman John Ray was the fountainhead of scientific ornithology, the author sets out to prove his case by way of a series of topics, e.g. migration, evolution, sex, territorialism; beginning with what Ray said about these and how Ray's ideas stood the test of time. Before Ray (and long after him) ornithological knowledge was mostly limited to the writings of Aristotle. One problem not adequately dealt with by Birkhead is whether subsequent, non-English investigators knew Ray's work and it appears to me that, however impressive Ray's curiosity, he serves primarily as an excuse for the topical organisation of the book. It is also fairly insular as most non-anglophone sources are used via previous English treatments and as a result much French or Dutch research is overlooked. He refers to Jac. Thijsse, somewhat dismissively, as a "Dutch schoolteacher," which even in 1906 (Birkhead's point of reference) he no longer was (he was then teaching biology to future teachers and Head of the Teacher's College in Amsterdam and thus today would be a Professor). But at the time Thijsse was Editor of the still extant nature mag. that he helped found. He was also secr. of the Dutch Assoc. for the Protection of Nature, of which he was a co-founder. As I wrote in two previous blogs, Thijsse inspired the sort of study that made Niko Tinbergen famous and thus helped create the field in which Birkhead is active. It also appears that Birkhead's real great ornithologist is his older centemporary David Lack, notwithstanding the fact that Lack often rejected earlier findings "out of hand" while later accepting either their importance or at least recognizing their proposer as a valued member of the tribe. I found the book slow going, which turned out a good thing, for not being able to work much outside there were many idle moments to fill. The illustrations are excellent. One new item, that answered one of my long standing questions, was the research indicating that birds pick partners that look like their siblings but are not identical and thus they avoid "inbreeding." My question arose from my having learned, partly from observation in "my" Dutch meadows, that birds return from their migration to the site they were born and also, from reading a study about prairie chickens that small isolated populations may die out as no "new blood" is available, for. ex. to maintain pr. ch. in 2 Illinois areas, they imported some from other states. When I "googled" kin-recognition as related to inbreeding it appeared to be a fertile field of study and no "one theory [that] fits all" has yet been found. But I was happy to find that birds recognize their kin. But back to the birds in my yard. [Addendum: I lost and can't find the reference, but a recent article (winter 2013) stated that birds also recognize siblings through smell, which would indicate that they have a memory of smell].
Caveat lector: As in all my garden observations the numbers are not exact science, they may even be thought anecdotal, for ex. when I write "3 Red-bellied Woodpeckers" it means that 3 were in my sight at one time, but as the birds are not marked I don't know whether the subsequent sighting of one or two are part of the three or additional ones. Of course if the three consist of one male and two females and later there are two males, there must be four Redbellies; etc. I observe throughout the day, mostly 15 minutes on the hour, sometimes longer as I have a coffee or read.
FEEDING: I began these Modest Birder blogs with questioning the maxim: "If you plant them, they will come" or the advertising that feeders will attract birds. In these blogs I was sceptical and after two years of observation, I am now only a little less so. March 2013: I deleted those early entries but was reminded of them by the arrival of an "Audubon Workshop" garden catalog featuring plants that will attract butterflies and birds (the plants were all more expensive than in nursery catalogs). The title of the catalog appears misleading as I can't find a connection to the A. Society. The content is also misleading as there are picture galleries throughout of birds that are not around at the same time or in the same place but the pix may make people believe that these birds will come "if they plant" the stuff for sale. Usually the "if you plant them" people promote (local) natives, unlike this catalog which assumes that people know what works in their area.
As I wrote in the Mod.B.(11), I had waited with putting up the feeders until I was pretty sure the usual winter residents were already present and put them up before Thanksgiving when my grandchildren would be here. This spring I kept them up through (the early) Easter as my grandkids were there again, but interestingly enough many winter residents had left by that time and so far only two of the summer residents (Towhee and Chipping sparrows) have arrived and the Towhees only picked at the food on the ground a few times, preferring to forage in the dead leaves at the edges of the woods. The Chipping Sparrows are also little interested in the feeders.
This winter I spent a good deal of time on observing aggressive behavior among birds of the same species (there was little) and among birds of different species which was strongest among the woodpeckers at the suet. Among them there was a clear pecking order with the Redbellies being at the top, followed by the Hairies, the larger Downies, the smaller Downies, the Nuthatches and very last the "really timid" Brown Creeepers. All of them left when Starlings arrived or stayed away when a Starling was on the suet. Only twice did I see a male Redbelly try to resist a Starling (in vain). The woodpeckers also did not allow another woodpecker on the suet, not even a conspecific one and also not in the last two weeks even though the resident Redbelly (1) and Downy (1 of each size) pairs would arrive near the suet tree together AND THE MALES MIGHT BRING A MORSEL TO THE NEARBY FEMALE. The most interesting was the fact that the 3 and now 2 Flickers foraged in the trees and on the ground (when there was no snow) but never came to the suet as they did last year when they, like the other woodpeckers also frequented the seed feeders. Interestingly enough, although the largest, the Flickers left when a Redb. arrived or waited until it had left.
The Hairies and Creepers had departed during the last week of March when it was unusually warm (but not as hot as in April and the week after Easter). I didn't refill the suet basket after Easter and the remaining woodpeckers and Nuthatches go to the seed, but mostly forage in the trees here and up and down the creek.
This winter I saw of the Cardinals, most of the time, only one male and one female and twice 2 males and once 2 females. In each case, even if they arrived close together the female left the feeder when a male landed on it and flew away or waited close by until the male had left. Last week, however, (the local) pair fed together for about 3 minutes. This week there have been 3 males singing and one afternoon two males were fighting above the creek. Like last year, this time when there were two females, I noticed them because they chased each other and one returned (which happened twice that morning). Female Cardinals have a song also and I wonder whether this territorialism is part of a female's make up just as it is of the males. I have not noticed it in other species in our woods.
Among the ground feeders, the Juncos are often the most "tolerant," which is no doubt why there can be so many of them (21 when the snows were highest). It was only towards the end that one or two would show some aggression and they would even chase each other around the bush or pick at each other while spiraling upward. And sometimes when one was alone on the dish with food that I had on a little table, it would try to keep others off, but back on the ground it would feed with the group. This may be a question of space, for even on the ground, with 10 or more feeding together, they would occasionally pick at each other when they came too close. The defense of space by a lone feeder when another arrived was most pronounced in the Song Sparrows; while smaller, the lone feeder would rush at an arriving White-throat who would then move to the edge of the spread out food. Among the White-throats (there were 9 for some time and 6 now) the males with the most striking facial pattern have become defenders of space but not only against other males but also the females, though it is not a very sustained action, maybe because the others usually feed at a large enough distance. Twice I saw a lone Song Sparrow rush at the viburnum and the brush pile behind it when a brown job flew into the viburnum too fast for me to recognize it. But the Song Sparrow would have none of it and chased the newcomer, once a Chipping Sparrow and the other time a White-throat away, though a little later these returned by way of a slow approach while foraging on the ground; the Song Sparrow let them be. In all these cases, excepting the dish defense, the aggression began or was more noticeable in the last few weeks with the approach of pair forming and departure.
One phenomenon that might be mentioned is that when a bird landed in full flight from some distance rather than from a nearby perch (when the flight would be slower and structured differently), most of the birds would give up their place and sometimes fly to a close branch, especially if it was a larger bird like a Redbelly or a Jay, but hardly ever if the newcomer was a mourning dove. Today (4/12) when there's no more suet and barely any food on the platform feeder or the ground, the Redbellies and Downies cling to the tube to feed. When the Redb. is there no other birds feed, not even on the opposite perches; when the small Downies are there (one at the time) Chickadees and Titmice will quickly steal a seed from an open perch.
In general the birds arrived to feed in the same "mixed flock" waves as the Fall migrants and most often from the same direction, i.e. from downstream, spreading out to forage in our trees and "spying out" the open space around the feeders before landing there. When not nervously flying up when a truck or school bus noisily slowed down on the road or exploding at the approach of a raptor, they would leave up the hill into the neighbor's yard and I got the feeling that the group was making a long circular movement that brought them back every hour or so. This pattern was broken during the inclement snows when they stayed very long to feed and would return less frequently. This "mixed flock" also included the sparrows though the Juncos, Whitethroats and Song Sparrows were often by themselves at daybreak and nightfall, apparently they didn't join the chickadees etc. until these arrived somewhat later when it was daylight. In fact the Whitethroats frequently stayed in the yews down by the creek to sleep during the day (and the night?), bundled fairly close together, three or more on a branch deep in the green from which they emerged by flying to the bare branches of the redbud above the yews before coming to the feeders. The morning doves preferred a snag whose tip rested in the creek, and sometimes I counted eleven huddled together, but during the day they also arrived when the "mixed flock" did and often as part of it.
As far as the food is concerned, I know that black sunflower and safflower seeds are favorites, that sorghums are less so, even among the sparrow like, and spelt is so-so but white mustard seems better than nijer for finches: last week I ran out of nijer and filled up the tube with white mustard and the finches fed more higher up than lower where the nijer languished. In fact when the tube was full with nijer, finches would mostly feed on the ground among the sparrows and juncos, while the latter would only once in a while go to the nijer tube. The "house" mix with or without nijer is preferred by all species, except the Brown creepers that never come to the seed feeders.
PAIR FORMING: As I wrote in early 2009, I had some problem deciding whether any of the Cardinals were residents or partial migrants from New York or so. Only an off-color male (dull pinkish red) that was thus easy to recognize, stayed around for sure. He has been there again since late January, but turned up only occasionally. Now he is paired and hangs out up the creek where he is occasionally confronted by a dark red male, that sings mostly in our bushes along the creek. Birkhead reports that Buffon, the 18th century French naturalist, once saw a very old bird that had actually turned gray; it's too anthopomorphic and I am sceptical, but could this paler cardinal no longer have the capacity to mould into full color? It appears that the dark red one and his female have been a pair at least since February when they began the alternating feeding patterns having arrived more or less together and leaving in the same direction. The paler one and probably his partner come to the feeder once in a while. The two pairs rarely meet there because they always perch first in the open some 20ft away as if to spy out the land, then fly to the Norway spruce and land on the feeder when the coast is clear. It's one way to avoid the competition though it's probably more to be safe. There is a 3d male singing near Rt 113 but apparently has a territory that is separated from us by the neighbor's earth moving equipment etc. Sometimes he and his mate fly across 113 where there are other neglected woods and evergreens near the adjoining office complex (where the local Mocking Bird hangs out).
It seems to me that the different woodpeckers are year around residents except for the Sapsuckers and Hairies though they may not move far away as there's a lot of suitable habitat along the Perkiomen and Schuylkill, both "scenic rivers" with forested banks. Occasionally a Hairy appears in May, but never the Sapsucker. Whether these were pairs, I don't know though there was one male and one female Sapsucker all winter, but never together and at intervals of sometimes more than a day. Once in a while there were 3 Hairies, but most often a male and female were more or less together, that is on different trees in our woods but in sight of each other and occasionally on different parts of thee suet tree. There were sometimes 3 Flickers, but lately there have only been a pair; the same goes for the smaller Downies and the Redbellies, in all cases the extra one was a female or immature and they disappeared when it got warmer and the snows had melted. The larger Downies were a pair all winter.
During the record snows of February there were several Titmice and Chickadees (incl. an uncommon Black-capped), but I'm pretty sure that there was one pair of each (that are still there) as two would come to the feeder at the same time if not always close together. The same goes for the Nuthatches. The two Brown Creepers acted pretty much like the Sapsuckers, and it was rare to see the two at the same time or on the same tree.
Only once were there three Song Sparrows, one of which turned out to be a Savannah on close inspection, complete with yellow lores. Thus the S.P. may have been the pair that is there now and the increasingly more sharply defined head and breast patterns on one may indicate the male in breeding plumage. The Juncos were present in uneven numbers, dark males outnumbering the more brownish juveniles or females. And I never clearly noticed pair like behavior among them. Several times a male was singing, but there were other males and brown ones nearby, none of which paid any attention. It's pretty much the same with the White-throats although now there are usually 6 of them, 3 males and three drab colored ones, perhaps females not yet changed (2 of the males showed their colors only in the last three days). Today, April 15, a day of declarations, 2 pairs of White-throats foraged jointly, one on the hanging feeders and one on the ground, they had arrived together and each pair landed in different parts of the spruce before descending to feed. When the 2 pairs got too close, the males went at each other and whirled upward in the typical aggression flight.
Some of the male Goldfinches are now in full breeding plumage, one already for 3 weeks, but the numbers remain uneven and no clear pair pattern has emerged, though every so often a male and female are not far apart, but they may fly off separately and in a different direction. With the Housefinches it is less complicated, even in February though there might be an uneven number (5 or 7) at least 2 pairs arrived regularly together and would feed on the platform feeder, on the ground or on opposite perches on the tube.
The general pattern suggest that among the winter residents some (local?)pairs are present but in a rather free association and the extras of a species disappear more or less when weather conditions make my fast food stations less of a necessity. Thus whatever may be the incident of infidelity, pair bonds seem established before the breeding season begins. In the case of the Whitethroats the likely pairs that were around left together, so that in their case the frequently encountered statement that males arrive on the breeding ground ahead of females may not apply.
I do not know, of course, whether some exchange of partners occurred when the extras were around, for example if one bird decides that a younger partner could improve the survival rate of the clutch. It's what ornithologists call "evolutionary strategy." I don't believe in the "evolutionary strategy" concept (it sounds too anthromorphic) when it comes to the species. I don't know whether the extras of residents were winter guests or juveniles of last year. Nor do I know whether the extras left or were the prey of the Cooper's that still comes several times a week (or more, but when I'm not observing); I've seen him carrying a dove and smaller birds to a tree up the creek and found Mourning Dove, Titmice and Junco feathers spread in a hawk's plucking pattern and I've see a Redtail devour a Junco right in the middle of the feeding area on the ground in front of my armchair. Come to think of it, the Cooper's may be the bird that is really attracted to our backyard by way of the feeders, if only indirectly through the songbirds that frequent them, for while a pair of Cooper's breed either along the Schuylkill or the Perkiomen, I have not noticed them in "our" woods during the summer
And talking about pairing: On January 4 during a week when the temperature rose above freezing (36!) only one day, a male Redbelly began to "drum" on a nearby dead branch, a few minute later a female joined in the drumming on another branch, then they got together and the male mounted her. Surprisingly enough a few hours later a Mourning Dove, feeding on the ground, "blew up" its neck, ran after another and mounted also. (Not a very promising "evolutionary strategy" or where they trying to stay warm? Perhaps I feed them too well?)
April 22: I took down and cleaned the feeders. Although they have been empty for almost 2 weeks the resident birds kept visiting them, interrupting their foraging in the trees, etc.
DEPARTING: One difference between modern humans and birds is that the latter do not throw "good-bye" parties or even just say a reverderci; they simply up and leave; their absence becomes memory. Nor does the availability of food keep them hanging around. I already mentioned the non-appearance of the Sapsuckers and Creepers around or before April 1 and about the same time the Juncos were gone, definitively on Easter Sunday when many pairs of eyes checked the feeders. The Juncos had become fewer gradually during March, but their absence was still pretty sudden and even a lone male that appeared in the late afternoon would have looked surprised had he been human: he left after about three minutes. Last year a few were still around on April 18 but then we did not have a run of beautiful weather and since temperature is said to affect migration, this may be the difference. On the same day last year there was still a pair of Hairies but this year no one saw any after Easter. Of the non-breeders only the White-throats are still around and in general all birds come less to the feeders; but my diary records that there were many clear days, even cold ones in January when that was also the case; the largest number of birds coming to the feeders, and at frequent intervals during the day, was on snow and other intemperate days. But since during the heart of winter the numbers were fairly steady it looks like the feeders only bring the local birds closer to the house when "fast food" is attractive in between periods of taking shelter in the evergreens. At all times when it was a clear day tree foragers would be busy in the trees and when the ground became visible the ground feeders also fed less on the food spread out in front of the window.
Something may be said about the arrival of summer residents and passing migrants, after all they depart from somewhere. The first male Towhee arrived two weeks ago, at least that's when it fed among the sparrows. I was probably pushing the season when on a sunny day earlier in March, I was "sure" I heard a chewink down the creek. The female arrived 4 days later. Both were earlier than the previous five years that I checked (last year it was 4/19. A Chipping Sparrow arrived at the same time, also earlier. On the Saturday before Easter a male Yellow-rumped Warbler flew into the spruce and first drew my attention by interrupting his gleaning for the typical fly-catcher like sallies after flying prey. Some years there were Yellow-rumps for most of the winter, but this year there were none after November. Because some oak species are already in full bloom, this may not be a good spring for warblers; they come usually late April and early May which is the normal hardwood blooming time. Last year there were 3 species on one day and 5 during the period. Now not one other bird is feeding that high up, not even the Chickadees and Titmice that during the winter sometimes were in the upper stories picking away at the very closed buds. On the 5th of April a male Pileated Woodpecker flew into a hickory from up the creek and then descended to two snags on which he foraged carefully all around the bottom parts; the flaming red tuft clashing vehemently with the redbud through which I observed him. He stayed for 2 days (last year one arrived from the same direction on the 4th, but left the same day). I think I heard a Phoebe down the creek in the last week of March, but saw one hawking from my amelanchier on April 5 (it left the next day); last year there were 2 on the 7th. During the early evening of April 16 a few thunder showers passed and left 1/5" of rain. The next day there was a pair of Palm Warblers foraging most of the day and on the 18th, after a day of more passing showers around us, there was a Prairie and a Black and White Warbler plus one that looked like a female Pine Warbler. (The Palm and Pine are new Yard List birds). On the 19th there were 3 Yellow-rumps (1 female) and a Nashville Warbler. The first oaks that bloomed are dropping the catkins, but several later oaks are blooming now; the hickories are just showing green.
These warblers demonstrate to me that no matter how many food sources you have in your yard, birds (especially migrants) appear but incidentally, for ex. when they meet a storm and stop their flight, at least that's how we had Yellows a few times, once 2 Kentuckies and last year a Golden Winged; the Yellow Rumps and Black and Whites are more or less annual in ones or twos, though when the oaks are in full bloom there may be more Yellow Rumps and they may linger. Think of the thousands of migrants overhead during the night and the hundreds of blooming oaks (from my chair alone I can see 100+ in the 80 degrees of the horizon, of which 18 (27 in total) in our own woods) plus hickories etc., and the rare sighting of warblers. For some reason it's different in the Fall when many more migrant passerines may turn up for a day or so.
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